1. Field
Embodiments relate generally to an image forming apparatus and a fuser controlling method thereof. More particularly, the present disclosure relates to an image forming apparatus for minimizing offset by controlling a fuser in a different controlling method according to a time interval of a printing paper entering the fuser, and a fuser controlling method thereof.
2. Description of the Related Art
An image forming apparatus is a device which prints printing data generated at a printing control terminal such as computer, onto a printing paper. Examples of the image forming apparatus include a copier, a printer, a fax machine, and a Multi Function Peripheral (MFP) integrating functions of the copier, the printer, and the fax machine in a single apparatus.
The image forming apparatus can form the image in various manners. One of the various methods is an electrophotographic method. The electrophotographic method forms the image by charging a photoconductor surface, forming a latent image through exposure, developing the latent image with toner, transferring the developed toner onto a printing paper, and fusing the image.
As such, the image forming apparatus can employ the unit for ultimately fusing the image onto the printing paper, which is referred to as a fuser.
In general, the fuser fixes the image on the printing paper by applying heat and pressure. In recent, by applying the (+) voltage to a pressure roller, the force of attaching the charged toner of the (−) polarity to the printing paper is increased.
Meanwhile, when the printing papers are input in succession, a conventional image forming apparatus continuously applies a bias voltage in the printing section. When the bias voltage is applied continuously, the bias voltage applied time extends and the (+) voltage overapplied is accumulated at a heat roller. When the (+) voltage overapplied is accumulated at the heat roller, the (−) charged toner is attracted to the heat roller and the toner on the heat roller can stain the next printing paper, which causes an offset.
To address the offset, a conventional method does not apply the bias voltage to the pressure roller when the printing paper does not pass through the fuser.
When the bias voltage is shut down when the printing paper does not pass through the fuser, it is difficult to apply the voltage to the heat roller or the pressure roller at the same time as the paper passes through in case where the interval of the printing papers is shortened to implement a rapid machine, the paper feeding is unstable.